Generate DDL from Hibernate Entities

DdlGenerator.java

import org.hibernate.boot.MetadataSources;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.hibernate.tool.schema.TargetType;

import java.util.EnumSet;
import java.util.HashMap;
import java.util.Map;

public class DdlGenerator {

    public static void main(String[] args) {
        Map settings = new HashMap();
        settings.put("hibernate.dialect", "org.hibernate.dialect.PostgreSQLDialect");

        MetadataSources metadata = new MetadataSources(new StandardServiceRegistryBuilder().applySettings(settings).build());
        for (Class clazz : new Class[]{
                ClassOne.class,
                ClassTwo.class
        }) {
            metadata.addAnnotatedClass(clazz);
        }
        SchemaExport schemaExport = new SchemaExport();
        schemaExport.createOnly(EnumSet.of(TargetType.STDOUT), metadata.buildMetadata());
    }

}